'Until men are seen as equally likely to take time off because of the child that they have brought into the world, this kind of covert, wink-wink discrimination will continue.' Photograph: Tara Moore/Getty Images

A few months ago, a friend of mine got married. To do this, she moved to London from Germany, leaving behind her friends, her family – and her job. She wasn't too worried about this: she'd built up more than a decade of experience and achievements. She could speak perfect English. She'd miss her family but financially, she'd be fine.

Unfortunately, London had other ideas. She went to interview after interview. They all ended in rejection.

Finally, she went to an interview where she was asked some odd questions. She was asked which part of London she lived in. She was asked what her husband did. And finally the interviewer just came out with it: "Look, your husband is obviously doing quite well for himself, you've just got married, why do you even want a job?"

Undoubtedly, that question contained the sexist (not to mention economically antiquated) idea that women just work for pin money. But it also hinted at another issue: the issue of babies. The issue of maternity leave. The issue of "why should I hire you when you'll probably just end up costing me thousands of pounds in wasted pay a few months down the line?"

Research into this area is of course welcome. But I can't help but feel that we are ignoring the most obvious reason why women are discriminated against in this way. The issue is at heart incredibly simple: it's about money.

Women from the age of 30 to 45 are viewed with suspicion and seen as a liability. They are a fecund cost waiting to happen. So why, these companies think, should we take the risk on this well-qualified woman, when we can place a safe bet on this man. He might not be as effective at the job, but at least he'll be around in six months' time. And so the cycle continues, with brilliant women floundering in their careers, overtaken by men not as a result of merit, but as a result of a shrewd cost decision. And perhaps the most irritating thing about this cycle is how easy it is to fix.

It is currently enshrined in law that women are the primary care-givers. Women get 26 weeks of ordinary maternity leave, and 26 weeks of additional maternity leave. Men get one or two weeks of ordinary paternity leave, and 26 weeks of additional paternity leave. There is no reason for this disparity, beyond a traditional notion that women are somehow more innately qualified than men to bring up children.

It's great that the government is finally sitting up and taking notice of this problem. It's great that it is seeing that legislating against discrimination doesn't mean that it stops. But what we need to see now is some action to change that. And splitting leave equally between the two parents of a child is the obvious and equitable way to do that.

Until men are seen as equally likely to take time off because of the child that they have brought into the world, this kind of covert, wink-wink discrimination will continue – and it will continue to affect women who don't intend to or can't have children, as much as those who do. If a company can't know either way, it is going to take the safer bet. And that bet is going to result in more women like my friend, who is still looking for a job, and still not finding one. I'm starting to wonder if she ever will.

• This article was amended on 5 November 2013. An error in the editing process led to us replacing the abbreviation EHRC with "European court of human rights" when in fact it stands for Equality and Human Rights Commission. This has now been corrected.